Acute oral toxicity and kinetic behaviors of inorganic layered nanoparticles

Layered double hydroxide (LDH) nanoparticles, also known as anionic clays, have attracted a great deal of interest for their potential as delivery carriers. Recent studies showed that LDH nanoparticles can efficiently deliver drugs or bioactive molecules into cells, which are highly related to their endocytic pathway. However, the efficient cell permeation capacity of LDH may also raise concern about their toxicity potential. In this study, the acute oral toxicity of LDH nanoparticles was assessed, and their kinetic behaviors, such as plasma concentration-time curve, tissue distribution, and excretion, were also evaluated in mice. No significant effects of oral LDH nanoparticles on behaviors, body weight gain, survival rate, and organosomatic index were observed up to the dose of 2000mg/kg for 14 days. Serum biochemical parameters did not significantly increase, indicating that LDH nanoparticles did not cause acute liver or kidney injury. Plasma concentration of LDH nanoparticles rapidly decreased within 30 min depending on exposure doses, but they did not accumulate in any specific organ. Their excretion via urine and feces was observed within 24 h. These findings suggest that LDH nanoparticles do not exhibit acute oral toxicity and favorable kinetic behaviors in mice and, therefore, will be promising candidates for biological and pharmaceutical applications.